Antitank mine fuse



May 22, 1945. A. ADELMAN I ANTI'IANK MINE FUSE Filed June 14, 1941 INVENTOR Arthur Adelma'n BY M/ 01 ATTORN S Patented May 22, 1945 l?" it writes ar ES PATENT @FFECE (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 2 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a fuse for an antitank mine or other explosive body.

It is an object of this invention to provide an improved form of fuse for any explosive body which is adapted to function when an exposed element of the fuse mechanism is engaged by a substantial force.

It is a further object of this invention to provide a fuse in which the spring elements will not be subject to fatigue in storage.

It is a further object of this invention to provide a novel form of anti-tank mine which may be readily and quickly assembled under field conditions.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing in which:

Fig. 1 is a longitudinal sectional view of the mine and fuse with the parts secured in unarmed position.

Fig. 2 is a plan view of the mine with the safety clip in position, and

Fig. 3 is a fragmentary sectional view showing an alternative form of assembling the primer.

Referring to the drawing by characters of reference, I indicates the explosive body of a mine adapted for use in defense against tanks and the like. This explosive body is formed with a cavity 2 in its upper surface for the reception of a fuse body 3. The cavity is provided with an inner flange forming a shoulder 2 or with a groove in its wall to engage the fuse-retaining means.

The detonating device comprises the body 3 in which axial cavities 4 and 5 connected by an opening 6 have been formed. The body 3 is further provided, near its upper end, with a plurality of radial cavities housing springs l and ball detents 8 which engage the fiarme formed in the cavity in the mine body for releasably maintaining the fuse body within the cavity in the mine. The lower cup-shaped cavity 4 is provided with a primer 9 of lead azide, mercury fulminate or other known fulminating compound which may be secured against the opening 6 by having a portion of the body 3 spun over the edge of a flanged primer containing cup l0. Figure 3 shows a modified method of securing a primer in the body of the fuse. In this case the opening 6 is made sule, for example, a standard center fire cartridge case with its rim engaging the upper surface of the partition between the cavities. An auxiliary primer charge may be loaded in the interior of the capsule. The remainder of the cavity 4 is loaded with a'booster H of tetryl or the like and may be sealed against the penetration of moisture by a disk l2 secured to the rim of the cavity.

The mechanical elements of the fuse are supported in the cavity 5 formed in the upper portion of the body 3. The filing mechanism consists of a firing member 13 slidable longitudinally in the cavity 5. In an axial bore in the member I3 a concentric sleeve member Hi is secured against relative longitudinal movement by shear pins l5. Inside the sleeve member and concentric therewith is a firing pin 16. Radial openings I! are formed in the walls of the sleeve It for the pas- Sage of retaining balls I8 engaging a conical face 19 surrounding the tip of the firing pin. A circumferential groove 20 is formed in the inner wall of'the member l3 which will receive the balls I8 when aligned with the openings ll. A spring 2| is confined under light pressure between the firing pin and the member 13. As this spring is not under high tension in storage it will not be subject to fatigue if stored over long periods of time. It will be seen that when any substantial load is applied to the member I3 the pins IE will be sheared and the resulting relative movement between 13 and the sleeve It will result in compression of the spring and in ultimate alignment of the groove 20 with the openings I'l. When this condition is reached the balls will be permitted to escape from their engagement with the firing pin which will be driven by the spring through the opening 6 to pierce the primer 9 and initiate the explosion of the mine proper. A seal 22 of thin metal or other like material is secured between the top of the body 3 and the upper end of the member l3 to form a moisture proof joint. A disk 23 is secured to the upper end of the member l 3 to receive the load either directly or from an auxiliary actuator element and to form a shoulder for the engagement of a safety clip 24 formed as shown in Fig. 2. The space allowed between the bottom of the cavity 5 and the lower end of the cylindrical member it insures that with the safety clip in position forces applied to the disc 23 will not be transmitted to the shear pins 15. A retaining cord 25 is secured to the clip at one end and at its other end to the disc 23. The fuse may be armed by withdrawing the clip, and the retaining cord ensures that the clip of the proper size to accommodate a rimmed cap- 55 will be readily available in case it is desired to return the mine to safe condition. For convenience in handling the mine a carrying ring 26 is provided.

Any desired form of auxiliary contact device may be adapted to cooperate with the disc 23 and enlarge the area from which the weight of a tank or other object will be effectively communicated to the firing member l3.

Although itis not the preferred method ofemploying th invention it is contemplated that the firing spring may be initially compressed and that the firing member serve principally as a releasing device. In either case the fuse itself wouldbe as suitable for use in bombs or otherv prajectiles as for use in anti-tank mines.

I claim: 7 V 1. A percussion fuse comprising a cylindrical casing member adapted to be inserted in an explosive body, a primer and aibooster'charge in said casing, a firing member slidable longitudisnallyuln :said :casing and-protruding ltherefrom, .1 saidfiring memberwbeing formed withan internal "boreshaving a..circum ferentialgroove in its, lower nportion,.a sleeve memberin the: internal "bore in -;saidi firing membeinand "retained therein against hlongitudinal :movement relative'to :the :;firing omember :by 1 shearablefmeans; radial: bores. in said sleevememberaopposing the walljof the. internal boreoof the firing .membergball Ldetents inv said oboresxanda firing pin.slidableilongitudinallyiin .i saidv sleeve rmember-andlheld in; engagement with adapted to be inserted into an explosive body, a

primer associated with said casing, a firing member slidable longitudinally in said casing and gprotruding therefrom, said firing member being formed with an internal cylindrical passage longitu'dina-lly thereof having a circumferential .grooveiinvits lower portion, a sleeve member in said internal passage of said firing member and retained therein against longitudinal movement relative to the firing member by shearable means, radial openings in said sleeve member and .so..disposed relative to said circumferential groove that they ar overlapped by the lower edge of saidrcircumferential groove, afiring pin slidable .llongitudinallyiin said sleeve member for striking 1' the rzprimer and having a shoulder thereon, 'ball detents in said radial :openingsabutting against .the' lower-e'clge'of said circumferentialrgroovetand said shoulder, and: spring means operative 'bentween'pthe said firing 'memberand the said firing "pin formurging the ,shoulderonrsaid firing .pin

'intoxcontact'with the said ball detents.

ARTHUR 

